Q. Why do I need to cite the sources I use in my research paper?

There are two main reasons you must cite the sources you have used in your research.     

 1.  To avoid plagiarism.  If you quote or re-state in your own words ideas, facts, opinions, or quotations from another source, you must give credit to the original source.  

2.  To help other researchers.  Providing a complete list of the works you have cited allows others to locate those sources.

When you incorporate another person's words or ideas into your paper, you must cite them.  You don’t need to cite generally-known facts that can be found in numerous places and are known by many people.  For example, you would not need to cite your source for a statement like "The capital of New York State is Albany" or "The Columbine High School massacre occurred in 1999."  These are well-known facts and dates that can be easily found in encyclopedias and other reference sources.

Sometimes it is difficult to figure out when you need to credit your source.  As a general guideline, if you knew a piece of information before you started doing research, usually you do not need to credit it.  If you are unsure, check with your instructor.  It is better to err on the side of caution and cite your source.